A new study by a nonprofit organization called the “Environmental Working Group” has studied the tap water of 35 US cities and found that 31 of the cities had tap water with detectable levels of hexavalent chromium. Hexavalent chromium is a suspected carcinogen, so this has set off alarm bells at the Group and in the environmental community.
The number of cities with health-threatening levels of the chemical in water supplies declines to 25 when one uses the recently-adopted California standard 0.06 parts per billion. Moreover, the American Chemical Council is contending that the California standard is ridiculously strict.
For one thing, according to the Council, some water that is supplied to consumers has naturally-occurring hexavalent chromium at higher levels than the new California standard. For another thing, claims the Council, present technology cannot even measure down to levels of 0.06 PPB (although as noted above the Environmental Working Group claims to have done this and, by so doing, to have reduced the number of “problem” water suppliers from 21 to 25).
Federal EPA has not yet weighed into this debate. At present, EPA merely regulates the amount of total chromium that can be in drinking water. Total chromium measures not only the suspect hexavalent chromium but also the beneficial chemical trivalent chromium (which helps the body metabolize glucose). EPA has indicated that the agency will study the matter and be ready with a conclusion next year regarding whether specifically to regulate hexavalent chromium and, if so, what level of the chemical to allow in drinking water.
As originally published in my column for Valley News Group of papers serving San Fernando Valley, California
